Many everyday processes depend upon expendable input materials normally in the gas phase. Automobiles, for example, depend upon oxygen normally extracted from the atmosphere, as needed, by compression in the engine cylinders. Compression is known to be energy expensive and subtracts from the useful shaft output from the engine. Significant engine performance improvements are available if the oxygen needed for combustion could be supplied by a stored source mounted with the engine. In other applications for internal combustion engines, stored oxygen, rather than atmospheric oxygen, must be used if the engine is to run at all. A submerged submarine with no snorkel must rely upon a stored source of oxygen if its Diesels are to be run. Otherwise, the electric engines must be used while the craft is submerged. Stored oxygen has been used for both automobile and submarine service where the oxygen is stored as a cryogenic liquid, a compressed gas, or as a chemical compound with available oxygen (i.e., hydrogen peroxide). All three methods have their advantages and problems. Compressed oxygen requires a heavy containing vessel that faces safety problems of fracture. Cryogenic oxygen requires expensive vacuum jacketed vessels that provide only limited protection from long term boil-off. Storage as a chemical with available oxygen presents problems of corrosion and safety (nitric acid, ammonium nitrate, hydrogen peroxide, etc.).
Oxygen for welding purposes is commercially stored and shipped as both a liquid or highly compressed gas. The same is true for oxygen in hospital service and for laboratory use.
Similar comments apply for nitrogen service. Atmospheric control in long range truck service is important for many applications. Thus, apples being shipped cross country may require a nitrogen rich atmosphere to reduce spoilage. Cryogenic nitrogen on-board the truck will serve this purpose. However, the apparatus necessary to store the cryogenic nitrogen is expensive and provides only a limited "shelf-life" for the stored cryogenic nitrogen.
In many applications, the safety of storing a highly compressed gas is limiting. In submarine service, for example, rupture of a vessel containing a highly compressed gas would mean certain disaster. The same would be true for an airplane application involving storing large amounts of highly compressed gas in the airplane.
The basic problem associated with storing a highly compressed gas is that nothing naturally will slow down the outrushing gas in case of vessel fracture. The potential energy of the compressed gas is released instantaneously and, thus, creates a near-infinite power or rate of energy release. If the outrushing gas can be slowed down, then the safety problem disappears. It is perfectly analogous to the gasoline situation. Burn a gallon of gasoline slowly, say in one hour, and nothing drastic happens. Burn the same gallon of gasoline in one second and a first order explosion will take place. The present invention provides a method and process wherein the maximum rate at which a compressed gas can leave a cylinder is limited by the action of an adsorbant material filling the vessel.